The Barrett REC7 is a gas-piston AR-15 in 5.56mm developed to meet the needs of special operations units seeking a cleaner-running alternative to the direct-impingement M4. Type: Rifle Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 2007, USA Weight: 68 oz Overall length: 35" Status: Active Intended use: Tactical